21429299 has 4 divisors (see below), whose sum is σ = 22689864. Its totient is φ = 20168736.

The previous prime is 21429293. The next prime is 21429311. The reversal of 21429299 is 99292412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21429299 - 2¹² = 21425203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21429293) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 630257 + ... + 630290.

It is an arithmetic number, because the mean of its divisors is an integer number (5672466).

Almost surely, 2^21429299 is an apocalyptic number.

21429299 is a deficient number, since it is larger than the sum of its proper divisors (1260565).

21429299 is a wasteful number, since it uses less digits than its factorization.

21429299 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1260564.

The product of its digits is 23328, while the sum is 38.

The square root of 21429299 is about 4629.1790848918. The cubic root of 21429299 is about 277.7597556959.

The spelling of 21429299 in words is "twenty-one million, four hundred twenty-nine thousand, two hundred ninety-nine".